Conventionally, an electric power steering apparatus has a motor, and the motor has an output shaft on one end and a control unit on the other end of its axial direction. For example, a patent document, Japanese Patent No. 5414869 (patent document 1) discloses a motor that has a bearing holder for separating the motor (i.e., a motor body or an output-shaft side of the motor) and its control unit at a position between the motor body and the control unit.
The output shaft of the motor in the patent document 1 is disposed to pierce the bearing holder, and is exposed from a control unit side of the bearing holder. Therefore, foreign matter may intrude into the control unit through a hole that pierces the bearing holder. That is, abrasion powder, grease, and the like produced from the rotation of the motor or used in the motor may intrude into a space that houses the control unit.